Isopropyl nitrate structure and vibrational spectrum analysis using quantum-chemical method

Abstract

© 2020 Trans Tech Publications Ltd, Switzerland. Calculation of molecular structure and related vibrational spectra of the isopropyl nitrate was carried out by means of density functional theory (DFT) by employing the Gaussian 03 mathematical package. The molecular geometries were fully optimized by using the Becke's three-parameter hybrid exchange functional combined with the Lee–Yang–Parr correlation functional (B3LYP) and using the 6-31G(d) basis set. By scanning the dihedral angles around C-O and C-C bonds, two energetically most favorable conformers of isopropyl nitrate-TG, GT forms were found. Calculations of the frequencies and forms of normal oscillations of the obtained forms of isopropyl nitrate are performed. The spectral features of the conformational state of isopropyl nitrate and the spectral effects of the formation of intramolecular H…ONO2 hydrogen bonds have been revealed.